common: Drop init.h from common header

Move this uncommon header out of the common header.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/board/ti/sdp4430/sdp.c b/board/ti/sdp4430/sdp.c
index 97da5cc..a5b3504 100644
--- a/board/ti/sdp4430/sdp.c
+++ b/board/ti/sdp4430/sdp.c
@@ -6,6 +6,7 @@
  * Steve Sakoman  <steve@sakoman.com>
  */
 #include <common.h>
+#include <init.h>
 #include <net.h>
 #include <twl6030.h>
 #include <asm/arch/sys_proto.h>